A review of the safety and efficacy of inhaled methoxyflurane as an analgesic for outpatient procedures

Methoxyflurane delivered via a hand-held inhaler is a proven analgesic which has been used in Australasia for emergency relief of trauma associated pain since the 1970s. The agent is self-administered by the patient under the supervision of trained personnel. More than 5 million patients have received inhaled methoxyflurane without significant side effects. Methoxyflurane is also licensed in Australasia for the relief of pain in monitored conscious patients requiring analgesia for minor surgical procedures. Recent clinical studies undertaken in a variety of outpatient settings, including colonoscopy, prostate biopsy, dental procedures, bone marrow biopsy, and the management of burns dressings, indicate that inhaled methoxyflurane has significant analgesic activity, without producing deep sedation or respiratory depression. Return to full psychomotor activity is rapid. Thus, methoxyflurane may be a suitable and well-tolerated alternative to traditional i.v. sedative agents for outpatient medical and surgical procedures. There are direct advantages to the patient in terms of rapid recovery and an early return to normal activities, and significant benefits for outpatient departments in terms of cost saving and rate of throughput. Further randomised controlled trials comparing the efficacy, safety, and cost-effectiveness of inhaled methoxyflurane against traditional i.v. sedative techniques are currently in progress.